Electric motor



(No Model.) 3 Sheets-Sheet 1. I

J. I. DENISON.

ELEGTRIO MOTOR.

No; 397,702. Patented Feb. 12, 1889.

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3 SheetsSheet 2.

(No Model.)

J. P. DENISON. ELECTRIC MOTOR.

Patented Feb. 12, 1889 N PETKIS, Photo-Wt. Wm D41.

(No'ModeL) 3 Sheets-Sheet 3.

J. F. DENISON.

ELECTRIC MOTOR. No. 397,702. Patented Feb. 12, 1889.

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UNITED STATES PATENT o JULIAN F. DENISOX, OF NEW HAX'EX, CONNEUFICUT.

ELECTRIC MOTOR.

SPECIFICATION forming part of Letters Patent No. 397,702, dated February 12, 1889. Application filed October 15, 1888. Serial No. 288,118. (No model.)

T0 (6 whom it may concern:

Be it known that I, J ULIAN F. Dnxrsoiv, of New Haven, in the county of New Haven and State of Connecticut, have invented a new Improvement in Electric Motors; and I do hereby declare the following, when taken in connection with accompanying drawings and the letters of reference marked thereon, to be a full, clear, and exact description of the same,'and which said drawings constitute part of this specification, and represent, in

Figure 1, a top view of the motor complete;

Fig. 2, a side view of the same; Fig. 3, an un- 1 der side view of the base, looking upward; i

Fig. 4, a transverse section cutting through the resistance-coils and looking toward the contacts; Fig. 5, a transverse section showing a plan view of the key as interlocked with the disk; Fig. 6, a detached view looking down upon the key, showing it engaged with the disk; Fig. 7, a portion of the disk and key, showing the key and disk as interlocked; Fig. 8, a diagram illustratin the conne(-ti ms; Fi 9 and 10, modifications.

This invention relates to an improvement in electric motors, with special reference to appliances for openin and closing the circuit through the motor.

Under the more general construction of 1 electric motors the current is led to the magreat at first as the motor starts and then is gradually reduced or wholly cut out, as circumstances may require. The resistance is usually applied or relieved by means of a lever like a switch-lever, which is free to be turned until the whole of the resistance is cut out or introduced, as the case maybe, the current being cut off or applied by an independent key, there being no substantial connection between the key and the device for operating the resistance to prevent either being operated independent of the other. The result of this is that if the current be cut off and the resistance be not turned in when the current be again applied the full force of the current will be admitted to the machine with disastrous et't'ects well known. Again, the switch or lever by which the resistance is applied or removed may be readily-turned from one extreme to the other, so that the resistance may be so rapidly turned off as to cause head, parallel with the disastrous results arising .trom a too sudden application of the current. Again, under the more general construction the devices for applying or reducing the resistance and the key to cut oil or apply the current are independent and outside of the machine itself.

The object of my invention is to avoid the difficulties before mentioned, and also to incorporate the resistance, the means for ap plying and cutting it off, and the key all in and as a substantial part of the machine itself; and the invention consists in the arrangement oi the resistanw-coils upon an axis, whereby the said coils may be rotated about the said axis to bring one or more of said coils into circuit, as the case may be, a disk upon the axis, about which the said coils rotate and which rotates therewith, with a key for opening and closing the circuit,whieh when the resistance is fully applied is free to move for the opening or closing of the circuit, but when closed the key engages the said disk of the ':tance .and so that the rotation of the said disk will hold the key in the circuit-closed position, the said rotation gradually taking the coils out of contact, thereby reducing the resistance, the 1: being held until, upon the return of the disk, the full resistance is again brought in, when the key will be automatically disengaged and free to chine through a resistance, which is very J open the circuit, and also in the arrangement of the resistance-coils and their operative mechanism within the base and as a part of the machine itself.

A represents the base, upon which the mechanism is arranged. This base is chambered upon its under side. The mechanism of the motor, as shown, is common and well known, and does not require nirticular description.

Longitudinally through the chamber-in the base is a shaft, B, supported in suitable bearin gs, C C, and which carries at one end a gear D, into which works a pinion, E, on the shaft of a hand-wheel, F, or other suitable handle, arranged outside the bed. The rotation of the said handwheel therefore through its pinion will communicate a rotation to the shaft B. The resistance is placed around the shaft B, and, as here represented, consists of two heads, G H, distant from each other, with the resistance-coils l extending from head to the shaft. These coils may be greater or less in number, according to circumstances or requirements of the apparatus. As represented in Fig. 4, six such coils are applied. A separate contact is provided for each coil, as represented in Fig. 4:, 2 3 et 5 (J 7 representing the contacts, and the connections with the respective coils are also shown in Fig. 4-. The contacts are of segment shape, and so as to present an interrupted cylindrical surface, as seen in Fig. 4, upon the outer head, and so as to revolve with a stationary contact, K, resting thereon, through which the current is carried to the machine. Asrepiesented in Fig. i, the resistaneeis wholly applied. Under the rotation of the shaft 13 and the coils in the direction indicated by the arrow, Fig. 4, the coils will be successively cut out, according to the extent of rotation imparted to the shaft B.

The pinion E of the hand-wheel F is made much smaller than the wheel D on the shaft, so that the rotation of the resistance-coils will be necessarily slow either in applying or cutting out the resistance.

L represents the key by which the circuit is closed or opened. It consists of a spindle arranged to slide parallel with the shaft 1 It is supported in suitable bearings, M, and extends outside the machine, terminating in a suitable head, N. The longitudinal movement of the key closes or opens the circuit, according to the direction of its movement and the arrangement of the connections therewith.

On the shaft B is a disk, 0, which is of a di ameter sufficiently great to extend into the path of the key Ii. At one point in the periphery of the disk a notch, a, is formed, which corresponds to the shape of the adjacent surface of the key-spindle, and when the disk is brought to the position that said notch 0 comes into line with the spindle of the key, as seen in Fig. 5, then the key is free to be moved out or in, as the case may be. In the side of the key next the periphery of the disk a notch, 11, is formed, which corresponds inwidth to the thickness of the disk 0, as seen in Figs. 3 and 6, this notch being in a position relative to the disk 0 so that when the circuit is closed the notch will stand in the path of the disk, as seen in Fig. 6. Then the key being held in thatposition, the rotation of the disk will cause the edge of the disk to pass into the notch in the key, as seen in Fig. 7, and interlock therewith, so as to prevent movement of the key so long as it shall remain interlocked with the disk; but when the disk is returned to bring its notch (1 into line with the spindle then the spindle is free to be moved to open the circuit.

A spring, P, is arranged upon the spindle, the tendency of which is to force it outward, the closing movement of the key being produced byan inward push against the spring P, as from the position Fig. 3 to that seen in Fig. 6. The notch (till the disk is in such position with relation to the key that when the resistance is all applied the said notch willbe in line with the key, so as to allow its free movement to close or open the circuit. \Vhen the key is in its normal position, as seen in Fig. 3-that is, with the circuit openthe disk interlocks with the body of the spindle, so that the rotation of the disk and of the resistance is positively prevented, and rotation of the disk and the resistance cannot occur until the key be forced. inward to bring its notch '1) into the path of the periphery of the disk 0, and, as seen in Fig. 6, consequently it is impossible to close the circuit, except when the resistance is fully applied, and when the circuit is closed it cannot remain closed until the disk is engaged with the key to hold it in the closed position, and the key once so engaged cannot be disengaged to open the circuit until the resistance be fully ap plied. Consequently the machine must normally stand with the resistance entirely applied, and it is impossible to close the circuit except when the resistance is so applied.

To make the engagement of the disk with the key automatic, so that as the key is pressed inward to close the circuit it will be caught in its extreme closed posiiion,l provide a spring to operate upon the disk, the tendency of which is to give to the disk a slight rotation to interlock it with the key whenvfree so to do. To thus apply the spring action to the disk, a stud, 71, projects from the disk or from the gear,which is the same thing, (see Fig. 3,) and in the path of this stud is a spring, i, located so that the stud will strike the spring j ust before the notch in the disk comes into line with the key, and so that by any further rotation of the disk to bring the notch of the disk into line wit-h the key the spring will be compressed. Then as the key is thrown or drawn outward to open the circuit it interlocks with the disk. and holds the disks with the spring thus compressed, and as indicated in Fig. Then when the key is forced inward to close the circuit the spring reacts, giving to the disk a slight rotative movement, so thatit will interlock with the notch of the key, and thus automatically engage the key when the circuit is closed.

In order that the rotation of the resistance IIO may be arrested when fully applied or when entirely cut out, I provide a stop, 112, against which the stud h or other suitable stop on. the disk will strike when the resistance is fully cut out. This stop occurs before the notch of the disk is brought intoline with the key, and this stop I preferably arrange so that the spring t may come to a hearing when fully compressed, and'so to positively arrest the further turning of the disk when its notch shall have been ln-onght into line with the key.

In Fig. 8 I lllllSlil'itlt} the connectionbetween the key and machine through the resistance. (Z represents one contact-spring in connection with the field-magnet, and e a second contactspring in connection with the resistance and armature, said two contact-springs being in the path of the key, and so that the movement of the key will bring it and the two springs into contact, as represented in broken lines. By the arrangement of the resistance and the connecting mechanism in the base of: the machine it becomes substantially a part of the machine, and yet practically does not increase the bulk or size of the machine.

The rotating resistance and the mechanism for interlocking with the key may be employed outside and independent of the motor. I therefore do not wish to be understood as limiting the invention to making the resistance a part of the motor itself.

I have represented the resistance-coils as being arranged about an axis and as provided with concentric contacts, whereby the resist ance is applied or removed by a rotative movement; but substantially the same result may be obtained by arranging the contacts in a longitudinal line, so as to slide, and as represented in Fig. 9, the same letters indicating the same parts. The contacts are shown as fully applied in solid lines, and in broken lines as cut out, the interlocking of the key being produced in substantially the same way, and as shown in that figure. Again, the rotative movement of the resistance may be retained and a sistance-coils, as indicated in slide being adapted to engage and disengage the key in substantially the same manner as that described for the rotative disk, and as clearly seen in Fig. 10. I therefore do not wish to be understood as limiting my invention to a necessary rotation of the contacts or to a rotative device to engage the key, it

only being essential that there shall be an interlockin mechanism between the resistancecoils and the key, whereby the key is free for movement to close or open the circuit: only when the resistance is fully applied.

I claim- 1. The combination of the rotating resist ance for electric motors with a disk arranged upon its axis and so as to revolve therewith, a key arranged to slide parallel with the axis of the resrtance and by which the circuit may be opened or closed, the said key standing within the line of the periphery of the said disk, the said disk constructed with a notch in its periphery corresponding to the surface of said key, and the key also constructed with a notch corresponding to the thickness of the disk, and which notch is brought into line with the disk when the circuit is closed, substantially as described, and so that the rotation ot the said disk causes it to interlock with the said key, substantially as and for the purpose described.

2. In an electric motor, the combination therewith of a resistance consisting of several coils arranged u of the machine pon an axis within the base and so as to rotate thereon,

slide introduced in place of i the disk, the said slide receiving a. reciproeating movement from the rotation of the re- Fig. 10, the said an independent contact for each coil of the resistance, the said contacts being of segment shape and arranged in line with each other, and so as to form a broken cylindrical surface concentric with the axis of rotation of the resistance, a contact stationary in the frame, against which the said contacts of the resistance will work,a key arrangm'l to slide in the base parallel with the axis of rotation of the I resistance, the said key being adapted under I its sliding movement to close or open the ciri cuit through the resistance, a disk on the axis I of said resistance and so as to revolve there- 1 with, the said key standing within the line of l the periphery of the said disk, the said disk constructed with a notch corresponding to l the said key when the resistance is fully apl plied, and the key constructed with a notch l with which the said disk may interlock under the rotation ot the resistance when the circuit is closed, substantially as and for t he purpose described. 1 3. In an electric motor, the combination of i a shaft supported in bearings in the base, a j resistance consistingot' several coils arranged l upon said shaft and so as to revolve therewith, an independent contact for each coil, the said contacts of segment shape and together forming an interrupted cylindrical surface r concentric with said shaft, a stationary contact arranged to bear upon the contacts of the y resistance, a key supported in hearings in the base and adapted to slide longitudinally to close and open the circuit, a disk on said shaft and so as to revolve therewith, the said disk and key constructed to be interlocked only upon the closing of the circuit or disengaged only upon the opening of the circuit, a gear l upon said shaft and so as to revolve therei with, with a pinion supported in said base arranged to work into said gear, the said pinion provided with a hand-wheel outside the base, whereby rotation may be imparted to said pin ion, substantt-illy as and for the pur- I [O I pose described.

i 1-. A resistance for electric motors, com- 1 posed of several coils, each coil having a conl tact independent ol the contacts of the other i coils, the several contacts adapted to move in i the same path and so as to present a broken or intcrruptwl surface, a stationary contact against which the several resistami'e-(mil com tacts will sin-cessively bear as the said contacts move, a key arranged to slide at right angles to the path of movement of said rei sistance-coil contacts, and mechanism, subl stant ially such as described, between said resistance-contacts and. said key to interlock said contacts with said key, substantially as specified, and whereby the key can only be moved to open or close the circuit when the l resistance is fully applied.

.l L'LIAN F. DENISOX.

lVitnesses:

JOHN E. EARLE, t FRED C. EARLE. 

